Axitinib in Metastatic Renal Cell Carcinoma

Targeted agents have revolutionized the management of metastatic renal cell carcinoma (RCC). Axitinib, an inhibitor of vascular endothelial growth factor receptor (VEGFR), has been an important addition to currently available therapies for advanced RCC. Its ability to inhibit VEGFRs at nanomolar concentrations distinguishes it as a potent tyrosine kinase inhibitor, with increased selectivity for VEGFR-1, 2, and 3 at clinically applicable concentrations. The phase 3 AXIS trial has established its superiority in prolonging progression-free survival (PFS) in previously treated RCC patients (median PFS 6.7 months for axitinib vs. 4.7 months for sorafenib). Common toxicities of axitinib include hypertension, diarrhea, nausea, hand-foot syndrome, fatigue, and hypothyroidism. Axitinib-induced diastolic blood pressure elevation may be associated with improved clinical outcome, likely reflecting the "on-target" effect of axitinib. Dose escalation to achieve therapeutic plasma drug levels is of considerable clinical interest. Although axitinib has established efficacy in patients treated with one previous agent, its use in the frontline setting is currently the subject of ongoing research.